Re: Trigger to create string to inverse SQL statement - Mailing list pgsql-general

thank you,

what do you mean use external program to build inverted queries. Do you have any examples?

Best,

Jacek  

2018-03-08 13:44 GMT+01:00 Francisco Olarte <folarte@peoplecall.com>:

Hello:

On Thu, Mar 8, 2018 at 1:32 PM, Łukasz Jarych <jaryszek@gmail.com> wrote:

i have a trigger which is added log history:

​I'll trust it is, but I cannot really see any thing in there, it may be better if in the future you used something like psql and pasted the data in a text format, which people with no-so-good eyesight like me can zoom in.​

 

It is possible to create additional column here with string with inversed SQL statement? 

So in this case: "Delete FROM t_trig WHERE ID=1". 

And what i want is to have possibility to loop through table and execute inversed sql statement for each row. 

​It should be. For inserts it is not that difficult, for updates YMMV, it is difficult to ​reverse a command exactly, but you get new and old values so you could write it. For deletes just reinsert. But I doubt there is a function which does it for you, you'll have to code something, and I suspect it may be easier to just capture op, old and new in your triggers and use an external program to build the inverted queries.

​Francisco Olarte.​